FLOATING ELECTROMAGNETIC FIELD GENERATOR SYSTEM AND METHOD OF CONTROLLING THE SAME
Floating electromagnetic field generator systems and methods are provided. The system comprises a surgical bed portion. The system also comprises a brace component disposed within the surgical bed portion. Additionally, the system comprises a first arm that is attached to the brace component. The first arm is positioned adjacent to the surgical bed portion. Additionally, the first arm has at least one field generator coil embedded therein. The system also comprises a second arm that is attached to the brace component. The second arm is positioned adjacent to the surgical bed portion. Additionally, the second arm has at least one field generator coil embedded therein. The second arm is positioned parallel to the first arm.
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 62/320,193 entitled “Floating Electromagnetic Field Generator System and Method of Controlling the Same,” filed Apr. 8, 2016, the disclosure of which is hereby incorporated by reference in its entirety.
BACKGROUND Field of the InventionThe field of the present application pertains to medical devices. More particularly, the field of the invention pertains to an electromagnetic tracking surgical system and a method of controlling the same.
Description of the Related ArtA surgical procedure may be performed on a patient using one or more surgical tools when the patient is placed on a surgical bed. The surgical tools may include endoscopes, catheters, ureteroscopes, or other similar devices. Endoscopy is a widely-used, minimally invasive technique for both imaging and delivering therapeutics to anatomical locations within the human body. Typically a flexible endoscope is used to deliver tools to an operative site inside the body—e.g., through small incisions or a natural orifice in the body—where a surgical procedure is to be performed. Endoscopes may have imaging, lighting and steering capabilities at the distal end of a flexible shaft enabling navigation of non-linear lumens or pathways.
SUMMARYExamples of a floating electromagnetic (EM) field generator system are provided. The floating EM field generator system may be used to support and/or develop arms disposed next to a surgical bed so as to prevent distortion of a field generator system due to bending of the surgical bed.
The placement of field generator coils within or adjacent to a surgical bed may be used for tracking surgical tools. In particular, when a sensor associated with a surgical tool interacts with an EM field generated by the field generator coils, the interactions may be measured to determine a location of the surgical tool.
However, the determination of a location of the surgical tool is based on a calibration of the field generator coils within an initial position. If the position of the field generator coils is altered, however, such as due to bending of the surgical bed, the interactions of the surgical tool sensor with the resulting EM field may result in measurements that do not correctly reflect the location of the surgical tool.
In order to avoid inaccurate determinations of surgical tool locations, structures are provided that fully or partially decouple arms used to embed field generator coils from a surgical bed. In this way, disturbances that occur at the surgical bed, such as bending, may be partially or fully prevented from affecting the EM field generator system.
In a first aspect of the invention, two arms that are adjacent to a surgical bed may be used to embed field generator coils. The arms may be supported using a brace portion. Additionally, the arms may be partially decoupled from the surgical bed so as to prevent, or partially prevent, the bending of the surgical bed from affecting the position of the arms.
In a second aspect of the invention, a base connector that connects two hinged arms, that are adjacent to a surgical bed, may rest against a base portion that is even with or below a level of a surgical bed. In this way, the base connector of the hinged arms may be in contact with the base portion independent of the placement or bending of the adjacent surgical bed. Additionally, the arms may be decoupled from the surgical bed so as to prevent, or partially prevent, the bending of the surgical bed from affecting the position of the arms.
In a third aspect of the invention, an intermediate connector that connects two hinged arms, that are adjacent to a surgical bed, may rest against a base portion that is even with or below a level of a surgical bed. In this way, the intermediate connector of the hinged arms may be in contact with the base portion independent of the placement or bending of the adjacent surgical bed. Additionally, the arms may be decoupled from the surgical bed so as to prevent, or partially prevent, the bending of the surgical bed from affecting the position of the arms.
In another aspect of the invention, a floating electromagnetic field generator system is provided. The system comprises a surgical bed portion. The system also comprises a brace component disposed within the surgical bed portion. Additionally, the system comprises a first arm that is attached to the brace component. The first arm may be positioned adjacent to the surgical bed portion. Additionally, the first arm may have at least one field generator coil embedded therein. The system also comprises a second arm that is attached to the brace component. The second arm may be positioned adjacent to the surgical bed portion. Additionally, the second arm may have at least one field generator coil embedded therein. The second arm may be positioned parallel to the first arm.
In some embodiments, the brace component is a circular brace component. In some embodiments, the first and the second arm are independent of movement the surgical bed portion. In further embodiments, the first and the second arm are independent of bending of the surgical bed portion.
In some embodiments, the first arm and the second arm are attached to the brace component using a hinge. In some embodiments, the first arm and the second arm are additionally attached using a connecting component. In further embodiments, the connecting component is a base connecting component. In additional further embodiments, the connecting component is an intermediate connecting component. In some embodiments, the intermediate connecting component has a width of three inches. In some embodiments, the intermediate connecting component has a width of five inches. In some embodiments, the intermediate connecting component has a width of between three inches and five inches.
In a further aspect of the invention, a floating electromagnetic field generator system is provided. The system comprises a first surgical bed portion that is connected to, and movable with respect to, a second bed portion. The system also comprises a brace component connected to the first surgical bed portion. Additionally, the system comprises a first arm that is attached to the brace component. The first arm may be positioned adjacent to the surgical bed portion, and the first arm having at least one field generator coil connected thereto. The system also comprises a second arm that is attached to the brace component. The second arm may be positioned adjacent to the surgical bed portion. Additionally, the second arm may have at least one field generator coil connected thereto.
In some embodiments, the first and second arm are partially independent of movement of the surgical bed portion. In some embodiments, the first and second arm are independent of movement of the surgical bed portion. In further embodiments, the first and the second arm are independent of bending of the surgical bed portion.
In some embodiments, each of the first arm and second arm have a plurality of field generator coils connected thereto. Additionally, in some embodiments, each of the first arm and the second arm has a plurality of field generator coils detachably attached thereto.
Another aspect of the invention provides a floating electromagnetic field generator system is provided. The system comprises a surgical bed portion. The system also comprises a brace component disposed within the surgical bed portion. Additionally, the system comprises a first hinged arm that is attached to the brace component, the first hinged arm positioned adjacent to the surgical bed portion, and the first hinged arm having at least one field generator coil embedded therein. The system also comprises a second hinged arm that is attached to the brace component, the second hinged arm positioned adjacent to the surgical bed portion, and the second hinged arm having at least one field generator coil embedded therein, the second hinged arm positioned parallel to the first hinged arm. Further, the system comprises a base connecting component that connects the first hinged arm and the second hinged arm.
In some embodiments, wherein the base connecting component is at a same level as the surgical bed. In some embodiments, the base connecting component is below the surgical bed. In some embodiments, the first and the second arm are independent of movement the surgical bed portion. In some embodiments, the first and the second arm are independent of bending of the surgical bed portion.
A further aspect of the invention provides a floating electromagnetic field generator system. The system comprises a surgical bed portion. The system also comprises a brace component disposed within the surgical bed portion. Additionally, the system comprises a first arm that is attached to the brace component, the first arm positioned adjacent to the surgical bed portion, and the first arm having at least one field generator coil embedded therein. The system further comprises a second arm that is attached to the brace component, the second arm positioned adjacent to the surgical bed portion, and the second arm having at least one field generator coil embedded therein, wherein the second arm is connected to the first arm using an intermediate connecting component.
In some embodiments, the intermediate connecting component is at a same level as the surgical bed. In some embodiments, the intermediate connecting component is below the surgical bed. In some embodiments, the first arm and the second arm are attached to the brace component using a hinge. In some embodiments, each of the first arm and second arm have a plurality of field generator coils connected thereto. In further embodiments, each of the first and second arm have a plurality of field generator coils detachably attached thereto. Additionally, in some embodiments, each of the first arm and the second arm have a plurality of field generator coils embedded within.
It shall be understood that different aspects of the invention can be appreciated individually, collectively, or in combination with each other. Other objects and features of the present invention will become apparent by a review of the specification, claims, and appended figures.
The invention will be described, by way of example, and with reference to the accompanying drawings, in which:
Although certain preferred embodiments and examples are disclosed below, the inventive subject matter extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses, and to modifications and equivalents thereof. Thus, the scope of the claims appended hereto is not limited by any of the particular embodiments described below. For example, in any method or process disclosed herein, the acts or operations of the method or process may be performed in any suitable sequence and are not necessarily limited to any particular disclosed sequence. Various operations may be described as multiple discrete operations in turn, in a manner that may be helpful in understanding certain embodiments; however, the order of description should not be construed to imply that these operations are order dependent. Additionally, the structures, systems, and/or devices described herein may be embodied as integrated components or as separate components.
Floating electromagnetic (EM) field generator systems for tracking a surgical tool relative to a surgical bed are provided. The floating EM field generator system may comprise arms. In particular, the arms that are next to a surgical bed may have EM field generator coils embedded therein. The EM field generator coils may be used to generate an EM field over at least a portion of the surgical bed. Additionally, the arms may be within a structure that is independent, or at least partially independent, from weight-bearing portions of the surgical bed. As such, in examples, floating EM field generator systems may be used to decouple the orientation of field generator coils from bending that may occur on a surgical bed.
In examples, an EM field generator may be used as one navigational component of a surgical tool tracking system that includes visual component and/or a fluoroscopic component. Additionally, systems provided that utilize three navigational components may be more accurate in tracking a surgical tool than navigational systems that only use one or two navigational components.
When using an EM field generator tracking system, a sensor associated with a surgical tool may be tracked based on interactions of the sensor with an electromagnetic field. In particular, a sensor associated with a surgical tool may be tracked when voltage is induced within a sensor coil that is placed within the electromagnetic field. In examples, the system provided may be used for alternating current (AC) EM tracking. In other examples, the system may be used for direct current (DC) EM tracking.
The electromagnetic field may be calibrated having a predetermined precision along a length of a surgical bed in the system. Small variations in position can be detected based on the sensor interaction with the electromagnetic field. The positional variations can have a spatial resolution of less than about 10 mm, 9 mm, 8 mm, 7 mm, 6 mm, 5 mm, 4 mm, 3 mm, 2 mm, or 1 mm. In some cases, the spatial resolution may be greater than about 10 mm. However, once a set of field generator coils are embedded, it is beneficial that the field generator coils remain in the same position, or at least the same position relative to the other field generator coils. If the field generator coils do not stay in the same position, the calibration of the field generator coils may be invalid, and the determined location of the sensor associated with the surgical tool may be incorrect.
Accordingly, the system may comprise a plurality of field generator coils embedded within arms that are associated with a surgical bed. The arms having the field generator coils embedded within may be disposed with respect to the surgical bed. In some examples, the field generator coils embedded within the arms may be placed with respect to, but decoupled from, the surgical bed. In this way, the field generator coils within the arms may be protected, or partially protected, from disturbances from the surgical bed.
Each field generator coil, or subset of field generator coils, may be configured to generate a magnetic field within a control volume. The control volume may be static. Alternatively, the control volume may be capable of changing dynamically (e.g., time-variable). The system may further comprise a position sensor disposed on a portion of the surgical tool. The position sensor may be configured to generate a sensor signal in response to the magnetic field when the position sensor is located inside the control volume. Additionally, the system may comprise an EM system controller configured to selectively activate one or more of the subsets of field generator coils based on the sensor signal. Further, the system may also comprise a plurality of calibration files that correspond to each individual configuration of activated coils.
In some cases, a physician may need to know the spatial information of an endoscope relative to the patient's body, using the surgical bed as a datum. The spatial information may include a spatial position and/or orientation of the endoscope in a three-dimensional coordinate system. One or more sensors may be attached to the endoscope to determine the spatial information. The sensors may include electromagnetic (EM) sensors configured to detect the spatial information of the endoscope, as well as movement of the endoscope, within the environment of the surgical bed. The EM sensors may be used in conjunction with a set of field generator coils that are disposed at or next to the surgical bed. The field generator coils may be configured to produce a calibrated (known) electromagnetic (EM) field over a working volume above and close to the surgical bed. The working volume may be defined as a three-dimensional space above the surgical bed where a portion of the patient's body is located. A region of interest on the patient's body (e.g., where a surgical procedure is to be performed) may be disposed within the working volume. When the endoscope moves within the working volume, the interaction of the EM sensors with the EM field results in electrical signals (e.g., voltages) being generated. The spatial information and/or movement of the endoscope can be determined by analyzing the electrical signals.
Current state-of-the-art field generator coils may be provided in different configurations. For example, in some cases, a flat configuration of field generator coils may be placed in a surgical bed directly under a patient. Alternatively, a box configuration of field generator coils may be placed externally on a side of the surgical bed or positioned above/over the patient. Optionally, a window configuration of field generator coils may be positioned under the surgical bed or under the patient. However, each of the above configurations has certain deficiencies. For example, use of fluoroscopy may be limited in the flat configuration because the generator coils constitute radio-opaque objects/regions that can obstruct fluoroscopic imaging (e.g., X-ray imaging). The box configuration may interfere with a physician's access to a patient since the coils are placed externally on the side of the surgical bed or positioned above/over the patient. In the window configuration, the positioning of coils under the surgical bed may result in mechanical and/or electromagnetic interference with other devices (e.g., motors for actuating the bed, linear actuator drives, radio-frequency (RF) circuits, etc.) that are also disposed under the surgical bed. Additionally, the positioning of coils under the patient may require an overall thickness of the bed to be increased, which results in larger form factor and higher manufacturing costs.
Additional drawbacks of one or more of the above coil configurations may include limited range of use. For example, the field generators in the above configurations typically generate a working volume of about 0.5 m×0.5 m×0.5 m, which is often insufficient to encompass a length or a width of a patient's body. In some instances, the surgical procedure may involve different parts of the patient's body that are spaced outside of the typical 0.5 m×0.5 m×0.5 m working volume. In those instances, movement of the coils around the surgical bed may be required, which may increase the mechanical complexity of the system and interfere with the physician's access to the patient.
Accordingly, it would be beneficial to have a floating EM field generator system and a method of controlling the system that provides improved navigation, ergonomics, and usability. A floating electromagnetic (EM) field generator system for tracking a surgical tool may be provided in accordance with another aspect of the invention. The system may comprise a plurality of subsets of field generator coils embedded within arms that are disposed with respect to a surgical bed. Each subset of field generator coils may be configured to generate a magnetic field within a control volume. A central portion of the surgical bed may be fluoroscopically transparent. The system may also comprise a position sensor disposed on a portion of the surgical tool. The position sensor may be configured to generate a sensor signal in response to the magnetic field when the position sensor is located inside the control volume. The system may further comprise an EM system controller configured to activate one or more of the subsets of field generator coils.
1. OverviewA floating electromagnetic field generator surgical system is provided in which field generator coils are embedded within arms of a surgical bed system. In examples, the field generator coils are placed in arms that are decoupled from movement and/or weight bearing on a bed portion of the surgical bed system. As a patient rests on a bed portion of the surgical bed, the arms containing the field generator coils may stay rigid. In other examples, the arms may be movable while keeping in steady position relative to each other. Using methods and systems discussed herein, field generator coils within arms of the surgical bed system may be relatively stable independent of a weight of a patient on a bed portion of the surgical bed system.
The placement of field generator coils in the disclosed configurations allows for unobstructed use of fluoroscopic imaging, and allows a physician to easily access the patient during a surgical procedure. Unlike some conventional systems, the field generator coils in the disclosed EM tracking surgical systems do not interfere with the physician's access to the patient. The integration of thick field generator coils within arms of the surgical bed system may also help to make beds thicker, which may allow for swivel to occur.
The disclosed configurations of field generator coils as embedded in arms of the surgical bed system also allow a plurality of EM fields to be selectively activated within different working volumes above the surgical bed. The selective activation of EM fields within the different working volumes can prevent interfering EM fields from being generated, and can reduce EM interference between the field generator coils and other devices. Reduction in EM interference can improve the accuracy and sensitivity with which a surgical tool (e.g., an endoscope having one or more EM sensors) can be tracked within the different working volumes above the surgical bed. Additionally, the disclosed configurations of field generator coils can extend the range of use of the system by a physician, since the working volumes can be configured to extend along a length of the surgical bed or in other configurations, depending on the requirements and complexity of the surgical procedure.
In additional examples, tracking of a surgical tool can be facilitated by activating different subsets of field generator coils. In examples, different subsets of field generator coils may be activated depending on the location of the surgical procedure relative to the surgical bed. Additionally, in examples, coils outside of the active subset(s) of field generator coils are inactive, thereby preventing interfering EM fields from being generated. In some examples, the working volumes above adjacent subsets of field generator coils may overlap so as to form a continuous global working volume along the length of the surgical bed. In addition, the calibration files needs to be swapped for each configuration.
For purposes of comparing various embodiments, certain aspects and advantages of these embodiments are described. Not necessarily all such aspects or advantages are achieved by any particular embodiment. Thus, for example, various embodiments may be carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other aspects or advantages as may also be taught or suggested herein.
2. Views of Floating EM Field Generator SystemThe brace component may help to support the arms so as to prevent bending and/or twisting of the arms when disturbances may occur further down the surgical bed. In examples, disturbances may occur in the surgical bed due to bending of the surgical bed due to the weight of a patient, hanging equipment, physician interaction, etc. In examples, bending and/or twisting of the arms may modify the EM field that is generated using field generator coils, thereby making the tracking of a surgical tool within the EM field less accurate. As such, decoupling the bending moment and/or lessening disruption of the surgical bed from the field generator coils embedded in arms of the surgical bed may improve accuracy of a tracking system that utilizes the EM field generated by the floating EM field generator system.
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As seen in
The surgical bed 2002 may be configured to support a patient. A physician may perform a surgical procedure on the patient while the patient is placed on the surgical bed 2002. In some embodiments, the surgical bed 2002 may comprise multiple sections that are movable relative to one another. In those embodiments, the patient's body can be moved into different positions by moving different sections of the surgical bed 2002 relative to one another. Alternatively, the surgical bed 2002 may be formed monolithically as a single rigid structure.
The plurality of field generator coils 2003 may be embedded or integrated within arms 2014 associated with the surgical bed 2002. For example, as shown in
In some examples, a plurality of working volumes 2112 may be generated using subsets of field generator coils 2104. This is shown in
The plurality of field generator coils 2003 may include, and can be grouped into, subsets as field generator coils 2104. For example, as shown in
Each subset of field generator coils 2104 may comprise a number of field generator coils. In
The field generator coils within each subset may be fixed in place relative to one another. For example, the field generator coils may be spaced apart by a predetermined distance and/or at a predefined pitch along the edges of the surgical bed 2002. Additionally, the field generator coils may be nominally fixed relative to the surgical bed 2002 in a global coordinate system. Any portion of the surgical bed 2002 may serve as an origin of the global coordinate system. In some embodiments, a datum point that lies substantially above a center portion of the surgical bed 2002 may serve as the origin of the global coordinate system. In those embodiments, the positions of the field generator coils may be defined relative to the datum point.
The EM system controller 2008 may be configured to provide electrical current pulses to the field generator coils 2003 to generate an EM field over the respective working volume 2112 above each subset of field generator coils 2104. The EM system controller 2008 can selectively activate (power on) different subsets of field generator coils 2104 to generate EM fields in different working volumes 2112 by controlling one or more switches in the switch module 2010. Electrical current pulses may be provided from the EM system controller 2008 to the different subsets of field generator coils 2104 via one or more switches in the switch module 2010.
The switches may include electronic switches such as power MOSFETs, solid state relays, power transistors, and/or insulated gate bipolar transistors (IGBTs). Different types of electronic switches may be provided for controlling current to a subset of field generator coils. An electronic switch may utilize solid state electronics to control current flow. In some instances, an electronic switch may have no moving parts and/or may not utilize an electro-mechanical device (e.g., traditional relays or switches with moving parts). In some instances, electrons or other charge carriers of the electronic switch may be confined to a solid state device. The electronic switch may optionally have a binary state (e.g., switched-on or switched-off). The electronic switches may be used to control current flow to the subsets of field generator coils. The operation of switches to selectively activate one or more subsets of field generator coils is described with reference to
The EM system controller 2008 can control the switches to activate: (1) the first subset of field generator coils 2104-1 to generate an EM field in the first working volume 2102-1, (2) the second subset of field generator coils 2104-2 to generate an EM field in the second working volume 2102-2, and/or (3) the third subset of field generator coils 2104-3 to generate an EM field in the third working volume 2102-3. In examples, the subsets of field generator coils may be activated simultaneously. In some examples, the subsets of field generator coils may be activated sequentially. For example, in some embodiments, the EM system controller 2008 can simultaneously activate all three subsets of field generator coils 2104 to create three separate EM fields in the respective working volumes 2112. Alternatively, the EM system controller 2008 can sequentially activate the first, second, and third subsets of field generator coils 2104-1, 2104-2, and 2104-3 to sequentially generate EM fields in the first, second, and third working volumes 2102-1, 2102-2, and 2102-3.
The EM system controller 2008 can be configured to activate one or more subsets of field generator coils without activating one or more other subsets of field generator coils. For example, in some embodiments, the EM system controller 2008 can activate only the first subset of field generator coils 2104-1 without activating the second and third subsets of field generator coils 2104-2 and 2104-3. Similarly, the EM system controller 2008 can activate only the second subset of field generator coils 2104-2 without activating the first and third subsets of field generator coils 2104-1 and 2104-3. Likewise, the EM system controller 2008 can activate only the third subset of field generator coils 2104-3 without activating the first and second subsets of field generator coils 2104-1 and 2104-2. In some cases, the EM system controller 2008 can activate the first and second subsets of field generator coils 2104-1 and 2104-2 without activating the third subset of field generator coils 2104-3. In other cases, the EM system controller 2008 can activate the second and third subsets of field generator coils 2104-2 and 2104-3 without activating the first subset of field generator coils 2104-1. Optionally, the EM system controller 108 can activate the first and third subsets of field generator coils 2104-1 and 2104-3 without activating the second subset of field generator coils 2104-2. Additional combinations (of the activation) of different subsets of field generator coils may be contemplated.
As previously described, the EM system controller 2008 can sequentially activate the first, second, and third subsets of field generator coils 2104-1, 2104-2, and 2104-3. In some embodiments, all three subsets of field generator coils may continue to be powered on after they have been sequentially activated. For example, the first subset of field generator coils 2104-1 may continue to be powered on after the second subset of field generator coils 2104-2 has been activated. The first and second subsets of field generator coils 2104-1 and 2104-2 may continue to be powered on after the third subset of field generator coils 2104-3 has been activated. Alternatively, in some embodiments, the first subset of field generator coils 2104-1 may be powered off after the second subset of field generator coils 2104-2 has been activated, and the second subset of field generator coils 2104-2 may be powered off after the third subset of field generator coils 2104-3 has been activated.
In some embodiments, the EM system controller 2008 may be located on the surgical bed 2002, for example on a base configured to support the surgical bed 2002. In some embodiments, the EM system controller 2008 may be located remotely from the surgical bed 2002. For example, the EM system controller 2008 may be disposed in a remote server that is in communication with the subsets of field generator coils 2004 and the switch module 2010. The EM system controller 2008 may be software and/or hardware components included with the server. The server can have one or more processors and at least one memory for storing program instructions. The processor(s) can be a single or multiple microprocessors, field programmable gate arrays (FPGAs), or digital signal processors (DSPs) capable of executing particular sets of instructions. Computer-readable instructions can be stored on a tangible non-transitory computer-readable medium, such as a flexible disk, a hard disk, a CD-ROM (compact disk-read only memory), and MO (magneto-optical), a DVD-ROM (digital versatile disk-read only memory), a DVD RAM (digital versatile disk-random access memory), or a semiconductor memory. Alternatively, the program instructions can be implemented in hardware components or combinations of hardware and software such as, for example, ASICs, special purpose computers, or general purpose computers.
The EM system controller 2008 may also be provided at any other type of external device (e.g., a remote controller for controlling the surgical bed 2002 and/or a surgical tool, any movable object or non-movable object, etc.). In some instances, the EM system controller 2008 may be distributed on a cloud computing infrastructure. The EM system controller 2008 may reside in different locations where the EM system controller 2008 is capable of controlling the switch module 2010 and selectively activating one or more subsets of field generator coils 2004 based on the spatial information of the position sensor 2016.
The position sensor 2016 may be disposed in or on a portion of a surgical tool. For example, in some embodiments, the position sensor 2016 may be disposed at a distal end of the surgical tool. Examples of surgical tools may include endoscopes, catheters, ureteroscopes, forceps, different types of scopes, or other similar devices or surgical accessories.
A position sensor, such as position sensor 2016, may be configured to generate an electrical signal (voltage or current signal) in response to EM fields generated field generator coils. Position sensor 2016 may be an EM sensor. As position sensor 2016 moves within a control volume 2012, the interaction of the position sensor 2016 with the EM field within the control volume 2012 may cause electrical signals to be generated. The electrical signals may vary as the position sensor 2016 moves between different locations within a control volume 2012. Additionally, electrical signals may vary as the position sensor 2016 moves between different control volumes. The EM system controller 2008 may be configured to receive electrical signals from the position sensor 2016. Additionally, the EM system controller 2008 may analyze the signals to compute a local position of the sensor 2016. The local position of the sensor 2016 may be computed relative to a local coordinate system. The local coordinate system may be defined at an active set of field generator coils corresponding to the control volume 2012 in which the position sensor 2016 is located.
The EM system controller 2008 may be further configured to compute a global position of the sensor 2016 relative to a global coordinate system. The global coordinate system may be defined at the surgical bed 2002 (e.g., above a center portion of the surgical bed 2002). The global position of the sensor 2016 may be computed based on: (1) the local position of the sensor 2016 within the control volume 2012 above an active set of field generator coils, and (2) the position of the active set of field generator coils relative to the surgical bed 2002. The global position of the sensor 2016 may be used to determine a position of a surgical tool relative to a patient on the surgical bed 2002.
The EM system controller 2008 may be configured to control the switch module 2010 based on one or more inputs. The control of the switch module 2010, and the selective activation of one or more field generator coils, may be manual and/or automatic.
In some embodiments, the EM system controller 2008 may control the switch module 2010 based on a user input corresponding to a selection of a region (or working volume 2112) of the surgical bed 2002 where tracking of a surgical tool is desired. For example, a physician may plan to perform a surgical procedure on a patient in a region within the first working volume 2112-1. Accordingly, the physician or the physician's assistant may provide an input to the EM system controller 2008 to activate the first subset of field generator coils 2104-1, so that movement of the surgical tool can be tracked within the first control volume via the position sensor 2016.
In some embodiments, the EM system controller 2008 may control the switch module 2010 based on an initialization input. The initialization input may cause the EM system controller 2008 to control the switch module 2010 to sequentially activate (cycle through) the subsets of field generator coils 2104, so as to determine: (1) whether the position sensor 2016 is present in any of the control volumes 2112, (2) in which control volume 2112 the position sensor 2016 is located if the position sensor 2016 is detected, and (3) the position of the sensor 2016 within the detected control volume 2112. Accordingly, the EM system controller 2008 can control the switch module 2010 to activate the subset of field generator coils 2104 corresponding to the control volume 2112 in which the position sensor 2016 is located, without activating the other subsets of field generator coils.
During the sequential activation (cycling) of the subsets of field generator coils 2104, the local position of the sensor 2016 relative to the local coordinate system of the working volume 2112 (where the sensor 2016 is located) may be determined. The local position of the sensor 2016 may be determined based on a distance between the sensor 2016 and a reference point in the local coordinate system. The reference point may lie anywhere in the local coordinate system. For example, in some embodiments, the reference point may be at an origin of the local coordinate system. One or more subsets of field generator coils 2104 may be activated based on the distance between the sensor 2016 and the reference point.
For example, when the reference point is an origin of a local coordinate system that is defined at a center of a control volume 2112, and the position sensor 2016 is located at or near the reference point, only the subset of field generator coils corresponding to that control volume 2112 may be activated. Conversely, when the position sensor 2016 is located far away from the reference point such that the sensor 2016 is proximate to another control volume 2112, adjacent subsets of field generator coils 2104 corresponding to both control volumes 2112 may be activated. It should be noted that the local coordinate system need not be defined at the center of a control volume 2112. In some other instances, the local coordinate system may be defined near an edge or corner of a control volume 2112. Any placement of the reference point and/or the local coordinate system within a control volume 2112 may be contemplated.
In some embodiments, the local position of the sensor 2016 may be determined based on distances between the sensor 2016 and a plurality of reference points in different local coordinate systems. The different local coordinate systems may lie in different control volumes 2012. The EM system controller 2008 may be configured to determine a minimum distance from those distances, and activate a subset of field generator coils 2104 corresponding to the control volume 2012 based on the minimum distance.
During a surgical procedure, the EM system controller 2008 may be configured to track the position and/or movement of the sensor 2016 within a control volume 2112 corresponding to an active subset of field generator coils 2104. As the position sensor 2016 moves between adjacent control volumes 2112, different subsets of field generator coils 2104 may be selectively activated to ensure that the sensor 2016 is continuously tracked, while at the same time reducing EM field interference effects.
3. Closed-Loop Positional and Speed FeedbackIn
As shown in
The EM system controller 2308 may be configured to control one or more switches to selectively activate one or more subsets of field generator coils 2304. For example, the EM system controller 2308 may selectively activate the first subset of field generator coils 2304-1 by closing the switch K1. Similarly, the EM system controller 2308 may selectively activate the second subset of field generator coils 2304-2 by closing the switch K2. Likewise, the EM system controller 2308 may selectively activate the third subset of field generator coils 104-3 by closing the switch K3. In some embodiments, the EM system controller 2308 may simultaneously activate two or more subsets of field generator coils 2304. For example, the EM system controller 2308 may simultaneously activate the first and second subsets of field generator coils 2304-1 and 2304-2 by closing the switches K1 and K2. Similarly, the EM system controller 2308 may simultaneously activate the first and third subsets of field generator coils 2304-1 and 2304-3 by closing the switches K1 and K3. Likewise, the EM system controller 2308 may simultaneously activate the second and third subsets of field generator coils 2304-2 and 2304-3 by closing the switches K2 and K3. Optionally, the EM system controller 2308 may simultaneously activate the first, second, and third subsets of field generator coils 2304-1, 2304-2, and/or 2304-3 by simultaneously closing the switches K1, K2, and/or K3, respectively. In some embodiments, the EM system controller 2308 may sequentially close the switches K1, K2, and/or K3. In some other embodiments, the EM system controller 2308 may close the switches K1, K2, and/or K3 in alternating manner. In some embodiments, the EM system controller 2308 may close the switches K1, K2, and/or K3 at a same frequency or at different frequencies. In some embodiments, the EM system controller 2308 may close/open the switches K1, K2, and/or K3 for different lengths of time, so as to activate or power off the subsets of field generator coils 2304 for different lengths of time.
5. Layout of Field Generator Coils and Working VolumesAs shown in
Each working volume 2412 may comprise a sub-volume threshold located within each working volume. The sub-volume threshold is located at a boundary between overlapping working volumes. The sub-volume threshold may correspond to a transition zone as the sensor moves between overlapping working volumes. For example, the first working volume 2412-1 may comprise a first sub-volume threshold 2413-1, and the second working volume 2412-2 may comprise a second sub-volume threshold 2413-2. The first sub-volume threshold 2413-1 may have a length L1′, and the second sub-volume threshold 2413-2 may have a length L2′. In some embodiments, the lengths L1′ and L2′ may be substantially the same. In other embodiments, the lengths L1′ and L2′ may be different. The widths of the first and second sub-volume thresholds may be the same, and the heights of the first and second sub-volume thresholds may be the same. In some alternative embodiments (not shown), the widths of the first and second sub-volume thresholds may be different. Optionally, the heights of the first and second sub-volume thresholds may be different.
Each working volume 2412 may further comprise a de-bounce threshold located within each sub-volume threshold. For example, the first working volume 2412-1 may comprise a first de-bounce threshold 2415-1, and the second working volume 2412-2 may comprise a second de-bounce threshold 2415-2. The second working volume may be activated once the sensor leaves the first de-bounce threshold and enters the second de-bounce threshold. Similarly, the first working volume may be activated once the sensor leaves the second de-bounce threshold and enters the first de-bounce threshold. Accordingly, the de-bounce thresholds may serve as “de-bouncing switches” for determining which working volume is to be activated. The first de-bounce threshold 2415-1 may have a length L1″, and the second de-bounce threshold 2415-2 may have a length L2″. In some embodiments, the lengths L1″ and L2″ may be substantially the same. In other embodiments, the lengths L1″ and L2″ may be different. The widths of the first and second de-bounce thresholds may be the same, and the heights of the first and second de-bounce thresholds may be the same. In some alternative embodiments (not shown), the widths of the first and second de-bounce thresholds may be different. Optionally, the heights of the first and second de-bounce thresholds may be different.
As shown in
Each subset of field generator coils 2404 may comprise a number of field generator coils 2403. The number of field generator coils 2403 in the subsets may be same or different. As shown in part B of
6. Selective Activation of Field Generator Coils with One Position Sensor
As shown in part A of
During a surgical procedure, the surgical tool 2517 may move to a different location, such that the position sensor 2516 may move to position B shown in part B of
Next, the surgical tool 2517 may move to a different location, such that the position sensor 2516 may move to position C shown in part C of
Next, the surgical tool 2517 may move to a different location, such that the position sensor 2516 may move to position D shown in part D of
7. Selective Activation of Field Generator Coils with a Plurality of Position Sensors
In
Additionally, in
As shown in part A of
During a surgical procedure, the surgical tool 2617 may move from the position shown in part A to the position shown in part B of
Next, the surgical tool 2617 may move from the position shown in part B to the position shown in part C of
Although
As shown in
A first working volume 2712-1 may be defined above the first subset of field generator coils 2704-1, and a second working volume 2712-2 may be defined above the second subset of field generator coils 2704-2, similar to the embodiment previously described in
As shown in
Each subset of field generator coils 2704 may comprise a number of field generator coils 2703. The number of field generator coils 2703 in the subsets 2704 may be same or different. In
As shown in
A first local coordinate system 2722-1 may be defined above a center portion of the first bed portion 2702-1. Likewise, a second local coordinate system 2722-2 may be defined above a center portion of the second bed portion 2702-2. The first local coordinate system 2722-1 may or may not have an origin that lies at a center portion of the first working volume 2712-1. Similarly, the second local coordinate system 2722-2 may or may not have an origin that lies at a center portion of the second working volume 2712-2. For example, as shown in part A of
Vectors may be defined between the global coordinate system 2720 and the local coordinate systems 2722-1 and 2722-2. For example, a vector T1 may be defined from the origin of the first local coordinate system 2722-1 to the origin to the global coordinate system 2720. A vector T2 may be defined from the origin of the second local coordinate system 2722-2 to the origin to the global coordinate system 2720. In some embodiments, another vector (not shown) may be defined from the origin of the first local coordinate system 2722-1 to the origin of the second local coordinate system 2722-2. The vectors T1 and T2 may be used to define the spatial relationship between the first working volume 2712-1 and the second working volume 2712-2. In particular, the vectors T1 and T2 may be used to define the spatial relationship between the first and second working volumes 2712-1 and 2712-2 relative to the datum point (origin of the global coordinate system 2720) as the first and second bed portions 2702-1 and 2702-2 move relative to each other.
As shown in part A of
Although part B of
In some embodiments, a position, shape, and/or size of the overlapping working volume 2714 between adjacent working volumes may change when the bed portions move relative to each other. For example, as shown in part A of
When the first bed portion 2702-1 rotates relative to the second bed portion 2702-2, the position, shape, and/or size of the first overlapping working volume 2714-1 may change. For example, as shown in part B of
As shown in
A first working volume 2812-1 and a second working volume 2812-2 may be associated with the first subset of field generator coils 2804-1 and the second subset of field generator coils 2804-2, respectively. In some embodiments, the first working volume 2812-1 may be a cylinder. The diameter of the cylinder may be about 5″, 6″, 7″, 8″, 9″, 10″, 11″, 12″, 13″, 14″, 15″, 16″ 17″, 18″, 19″, 20″, 21″, 22″, 23″, 24″, 25″, or greater than 25″. The height of the cylinder may be about 5″, 6″, 7″, 8″, 9″, 10″, 11″, 12″, 13″, 14″, 15″, 16″ 17″, 18″, 19″, 20″, 21″, 22″, 23″, 24″, 25″, or greater than 25″. In some examples, a cylinder may have a minimum diameter and height of about 5″×5″. In other examples, a cylinder may have a maximum distance and height of about 25″×25″. Optionally, in some examples, each of the diameter and height of a cylinder may be less than 5″, or greater than 25″. Optionally, the first working volume 2812-1 may be a cuboid. The length of the cuboid may be about 5″, 6″, 7″, 8″, 9″, 10″, 11″, 12″, 13″, 14″, 15″, 16″ 17″, 18″, 19″, 20″, 21″, 22″, 23″, 24″, 25″, or greater than 25″. The width of the cuboid may be about 5″, 6″, 7″, 8″, 9″, 10″, 11″, 12″, 13″, 14″, 15″, 16″ 17″, 18″, 19″, 20″, 21″, 22″, 23″, 24″, 25″, or greater than 25″. The height of the cuboid may be about 5″, 6″, 7″, 8″, 9″, 10″, 11″, 12″, 13″, 14″, 15″, 16″ 17″, 18″, 19″, 20″, 21″, 22″, 23″, 24″, 25″ or greater than 25″. In some examples, a cuboid may have a minimum length, width, and height of about 5″×5″×5″. In other examples, a cuboid may have a maximum length, width, and height of about 25″×25″×25″. Optionally, in some examples, each of the length, width, and height of a cuboid may be less than 5″, or greater than 25″. The second working volume 2812-2 may or may not have the same shape and/or dimensions as the first working volume 2812-1. Any shape and/or dimensions for the first and second working volumes may be contemplated.
As shown in
As shown in
The first bed portion 2902-1 may further include two arms 2906 that are adjacent to the surgical bed. As previously described, by placing a plurality of field generator coils within arms 2906 adjacent to the surgical bed 2902 (e.g., the first bed portion 2902-1), unobstructed use of fluoroscopy can be achieved to image at least a portion of a patient's body. Each row 2906 may have a width of t that is associated with an area of fluoro obstruction. In some embodiments, the width t may be less than or equal to about 2 inches. It should be noted that rows 2906 constitute areas of fluoroscopy obstruction, since the field generator coils are radio-opaque.
The bed portion 3002-1 may further include two parallel rows 3006 on its edges. In examples, the two parallel rows may comprise arms that are adjacent to the surgical bed. The arms may be decoupled from the surgical bed such that weight of a patient that bends a surgical bed may not adversely affect the placement of field generator coils within arms adjacent to the surgical bed. As previously described, by placing a plurality of field generator coils along two arms adjacent to the surgical bed, unobstructed use of fluoroscopy can be achieved to image at least a portion of a patient's body. Each row 3006 may have a width of t′. In some embodiments, the width t′ may be less than or equal to about 3.025 inches. The two parallel rows 3006 may be separated by a distance wl. In some embodiments, the distance wl may be about 15.75 inches. Additionally, rows 3006 may constitute areas of fluoroscopy obstruction, since the field generator coils are radio-opaque.
As shown in
As used herein A and/or B encompasses one or more of A or B, and combinations thereof such as A and B. It will be understood that although the terms “first,” “second,” “third” etc. may be used herein to describe various elements, components, regions and/or sections, these elements, components, regions and/or sections should not be limited by these terms. These terms are merely used to distinguish one element, component, region or section from another element, component, region or section. Thus, a first element, component, region or section discussed below could be termed a second element, component, region or section without departing from the teachings of the present invention.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” or “includes” and/or “including,” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components and/or groups thereof.
Furthermore, relative terms, such as “lower” or “bottom” and “upper” or “top” may be used herein to describe one element's relationship to other elements as illustrated in the figures. It will be understood that relative terms are intended to encompass different orientations of the elements in addition to the orientation depicted in the figures. For example, if the element in one of the figures is turned over, elements described as being on the “lower” side of other elements would then be oriented on the “upper” side of the other elements. The exemplary term “lower” can, therefore, encompass both an orientation of “lower” and “upper,” depending upon the particular orientation of the figure. Similarly, if the element in one of the figures were turned over, elements described as “below” or “beneath” other elements would then be oriented “above” the other elements. The exemplary terms “below” or “beneath” can, therefore, encompass both an orientation of above and below.
While preferred embodiments of the present invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from the invention. It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. Numerous different combinations of embodiments described herein are possible, and such combinations are considered part of the present disclosure. In addition, all features discussed in connection with any one embodiment herein can be readily adapted for use in other embodiments herein. It is intended that the following claims define the scope of the invention and that methods and structures within the scope of these claims and their equivalents be covered thereby.
Claims
1. A floating electromagnetic field generator system, comprising:
- a surgical bed portion;
- a brace component disposed within the surgical bed portion;
- a first arm that is attached to the brace component, the first arm positioned adjacent to the surgical bed portion, and the first arm having at least one field generator coil embedded therein; and
- a second arm that is attached to the brace component, the second arm positioned adjacent to the surgical bed portion, and the second arm having at least one field generator coil embedded therein, the second arm positioned parallel to the first arm.
2. The system of claim 1, wherein the brace component is a circular brace component.
3. The system of claim 1, wherein the first and the second arm are independent of movement the surgical bed portion.
4. The system of claim 3, wherein the first and the second arm are independent of bending of the surgical bed portion.
5. The system of claim 1, the first arm and the second arm are attached to the brace component using a hinge.
6. The system of claim 1, wherein the first and the second arm are additionally attached using a connecting component.
7. The system of claim 6, wherein the connecting component is a base connecting component.
8. The system of claim 6, wherein the connecting component is an intermediate connecting component.
9. The system of claim 8, wherein the intermediate connecting component has a width of three inches.
10. The system of claim 8, wherein the intermediate connecting component has a width of five inches.
11. The system of claim 8, wherein the intermediate connecting component has a width between three inches and five inches.
12. A floating electromagnetic field generator system, comprising:
- a first surgical bed portion that is connected to, and movable with respect to, a second surgical bed portion;
- a brace component connected to the first surgical bed portion;
- a first arm that is attached to the brace component, the first arm positioned adjacent to the surgical bed portion, and the first arm having at least one field generator coil connected thereto; and
- a second arm that is attached to the brace component, the second arm positioned adjacent to the surgical bed portion, and the second arm having at least one field generator coil connected thereto.
13. The system of claim 12, wherein the first and the second arm are partially independent of movement the surgical bed portion.
14. The system of claim 12, wherein the first and the second arm are independent of movement the surgical bed portion.
15. The system of claim 14, wherein the first and the second arm are independent of bending of the surgical bed portion.
16. The system of claim 12, wherein each of the first arm and second arm have a plurality of field generator coils connected thereto.
17. the system of claim 16, wherein each of the first and second arm have a plurality of field generator coils detachably attached thereto.
18. The system of claim 16, wherein each of the first arm and the second arm have a plurality of field generator coils embedded within.
19. A floating electromagnetic field generator system, comprising:
- a surgical bed portion;
- a brace component disposed within the surgical bed portion;
- a first hinged arm that is attached to the brace component, the first hinged arm positioned adjacent to the surgical bed portion, and the first hinged arm having at least one field generator coil embedded therein;
- a second hinged arm that is attached to the brace component, the second hinged arm positioned adjacent to the surgical bed portion, and the second hinged arm having at least one field generator coil embedded therein, the second hinged arm positioned parallel to the first hinged arm; and
- a base connecting component that connects the first hinged arm and the second hinged arm.
20. The system of claim 19, wherein the base connecting component is at a same level as the surgical bed.
21. The system of claim 19, wherein the base connecting component is below the surgical bed.
22. The system of claim 19, wherein the first and the second arm are independent of movement the surgical bed portion.
23. The system of claim 22, wherein the first and the second arm are independent of bending of the surgical bed portion.
24. A floating electromagnetic field generator system, comprising:
- a surgical bed portion;
- a brace component disposed within the surgical bed portion;
- a first arm that is attached to the brace component, the first arm positioned adjacent to the surgical bed portion, and the first arm having at least one field generator coil embedded therein; and
- a second arm that is attached to the brace component, the second arm positioned adjacent to the surgical bed portion, and the second arm having at least one field generator coil embedded therein, wherein the second arm is connected to the first arm using an intermediate connecting component.
25. The system of claim 24, wherein the intermediate connecting component is at a same level as the surgical bed.
26. The system of claim 24, wherein the intermediate connecting component is below the surgical bed.
27. The system of claim 24, the first arm and the second arm are attached to the brace component using a hinge.
28. The system of claim 24, wherein each of the first arm and second arm have a plurality of field generator coils connected thereto.
29. The system of claim 28, wherein each of the first and second arm have a plurality of field generator coils detachably attached thereto.
30. The system of claim 28, wherein each of the first arm and the second arm have a plurality of field generator coils embedded within.
Type: Application
Filed: Feb 21, 2017
Publication Date: Oct 12, 2017
Patent Grant number: 11324554
Inventors: Jason Lee (Milpitas, CA), Christopher Sramek (Half Moon Bay, CA), Gregory J. Kintz (Santa Cruz, CA), David S. Mintz (Mountain View, CA), Alan Yu (Union City, CA)
Application Number: 15/438,589